/Engine/Plugins/Enterprise/VariantManagerContent/Source/VariantManagerContent/Public/Variant.h
Sets the thumbnail to use for this variant. Can receive nullptr to clear it.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category="Variant|Thumbnail") void SetThumbnailFromTexture ( [UTexture2D](API\Runtime\Engine\Engine\UTexture2D) * NewThumbnail )